curl_version_info.3: fix ssl_version description

Reported-by: Vincas Razma
Fixes #2364
diff --git a/docs/libcurl/curl_version_info.3 b/docs/libcurl/curl_version_info.3
index 4412071..e69e312 100644
--- a/docs/libcurl/curl_version_info.3
+++ b/docs/libcurl/curl_version_info.3
@@ -5,7 +5,7 @@
 .\" *                            | (__| |_| |  _ <| |___
 .\" *                             \___|\___/|_| \_\_____|
 .\" *
-.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
 .\" *
 .\" * This software is licensed as described in the file COPYING, which
 .\" * you should have received as part of this distribution. The terms
@@ -169,8 +169,9 @@
 .IP CURL_VERSION_BROTLI
 supports HTTP Brotli content encoding using libbrotlidec (Added in 7.57.0)
 .RE
-\fIssl_version\fP is an ASCII string for the OpenSSL version used. If libcurl
-has no SSL support, this is NULL.
+\fIssl_version\fP is an ASCII string for the TLS library name + version
+used. If libcurl has no SSL support, this is NULL. For example "WinSSL",
+\&"SecureTransport" or "OpenSSL/1.1.0g".
 
 \fIssl_version_num\fP is always 0.